7. A 0.5-kg puck is traveling at 3.0 m/s. It strikes a 1.0-kg puck, which is
stationary. The two pucks stick together. What is their final speed after
collision?
A. 1.0 m/s
OB. 2.0 m/s
OC. 2.5 m/s
OD.3.0 m/s
*
1 point